{
  "api_version": "1",
  "request": {
    "url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Observational+study&page=6",
    "query": {
      "intervention": "Observational study",
      "page": 6
    },
    "page_size": 10
  },
  "pagination": {
    "page": 6,
    "page_size": 10,
    "total_count": 4385,
    "total_pages": 439,
    "next_page_url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Observational+study&page=7&page_size=10",
    "previous_page_url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Observational+study&page=5&page_size=10"
  },
  "source": "remote",
  "last_synced_at": "2026-10-17T11:57:59.047Z",
  "attribution": "Data derived from public ClinicalTrials.gov records. The official record at https://clinicaltrials.gov/ remains the source of truth for current availability, contacts, and full study details.",
  "notes": [
    "This endpoint exposes only public summary fields — no participant contact emails, phone numbers, or scraped investigator contact details.",
    "For contact information and full protocol detail, follow each trial's `official_url` to the ClinicalTrials.gov record.",
    "This API is a navigational aid. It does not provide medical advice, eligibility determinations, or compensation guarantees."
  ],
  "trials": [
    {
      "nct_id": "NCT04270604",
      "title": "Biological Sample Collection for Research and Biobanking",
      "overall_status": "TERMINATED",
      "study_type": "OBSERVATIONAL",
      "phases": [],
      "conditions": [
        "Parkinson Disease",
        "Diabetes Mellitus, Type 1",
        "Macular Degeneration",
        "ALS",
        "Cancer",
        "Alzheimer Disease",
        "Huntington Disease"
      ],
      "interventions": [
        {
          "name": "Biological sample collection",
          "type": "OTHER"
        }
      ],
      "intervention_types": [
        "OTHER"
      ],
      "sponsor": "New York Stem Cell Foundation Research Institute",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "1 Month",
        "maximum_age": "100 Years",
        "sex": "ALL",
        "summary": "1 Month to 100 Years"
      },
      "enrollment_count": 1279,
      "start_date": "2012-02-06",
      "completion_date": "2023-11-27",
      "has_results": false,
      "last_update_posted_date": "2024-08-02",
      "last_synced_at": "2026-10-17T11:57:59.047Z",
      "location_count": 1,
      "location_summary": "New York, New York",
      "locations": [
        {
          "city": "New York",
          "state": "New York"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT04270604"
    },
    {
      "nct_id": "NCT07566793",
      "title": "Validation of Effectiveness on NaturalCycles Users",
      "overall_status": "RECRUITING",
      "study_type": "OBSERVATIONAL",
      "phases": [],
      "conditions": [
        "Contraception"
      ],
      "interventions": [
        {
          "name": "Log daily intercourse information",
          "type": "BEHAVIORAL"
        },
        {
          "name": "Natural Cycles application",
          "type": "DEVICE"
        }
      ],
      "intervention_types": [
        "BEHAVIORAL",
        "DEVICE"
      ],
      "sponsor": "Natural Cycles",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "35 Years",
        "sex": "FEMALE",
        "summary": "18 Years to 35 Years · Female only"
      },
      "enrollment_count": 2000,
      "start_date": "2026-04-28",
      "completion_date": "2027-12",
      "has_results": false,
      "last_update_posted_date": "2026-07-01",
      "last_synced_at": "2026-10-17T11:57:59.047Z",
      "location_count": 1,
      "location_summary": "New York, New York",
      "locations": [
        {
          "city": "New York",
          "state": "New York"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT07566793"
    },
    {
      "nct_id": "NCT01968226",
      "title": "TRACER RGD-K5 Carotid Plaque Imaging Study",
      "overall_status": "TERMINATED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Carotid Artery Disease",
        "Carotid Stenosis"
      ],
      "interventions": [
        {
          "name": "[F-18] RDG-K5",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "The Cleveland Clinic",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 3,
      "start_date": "2013-11",
      "completion_date": "2016-06",
      "has_results": true,
      "last_update_posted_date": "2017-09-12",
      "last_synced_at": "2026-10-17T11:57:59.047Z",
      "location_count": 1,
      "location_summary": "Cleveland, Ohio",
      "locations": [
        {
          "city": "Cleveland",
          "state": "Ohio"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01968226"
    },
    {
      "nct_id": "NCT02275533",
      "title": "Testing Nivolumab to Prevent Disease From Coming Back After Treatment in Patients With Acute Myeloid Leukemia, REMAIN Trial",
      "overall_status": "ACTIVE_NOT_RECRUITING",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Acute Myeloid Leukemia"
      ],
      "interventions": [
        {
          "name": "Biospecimen Collection",
          "type": "PROCEDURE"
        },
        {
          "name": "Bone Marrow Biopsy",
          "type": "PROCEDURE"
        },
        {
          "name": "Clinical Observation",
          "type": "OTHER"
        },
        {
          "name": "Echocardiography Test",
          "type": "PROCEDURE"
        },
        {
          "name": "Nivolumab",
          "type": "BIOLOGICAL"
        }
      ],
      "intervention_types": [
        "PROCEDURE",
        "OTHER",
        "BIOLOGICAL"
      ],
      "sponsor": "National Cancer Institute (NCI)",
      "sponsor_class": "NIH",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 82,
      "start_date": "2015-07-02",
      "completion_date": "2026-10-08",
      "has_results": true,
      "last_update_posted_date": "2026-05-28",
      "last_synced_at": "2026-10-17T11:57:59.047Z",
      "location_count": 45,
      "location_summary": "Birmingham, Alabama • Tucson, Arizona • Duarte, California + 34 more",
      "locations": [
        {
          "city": "Birmingham",
          "state": "Alabama"
        },
        {
          "city": "Tucson",
          "state": "Arizona"
        },
        {
          "city": "Tucson",
          "state": "Arizona"
        },
        {
          "city": "Duarte",
          "state": "California"
        },
        {
          "city": "La Jolla",
          "state": "California"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT02275533"
    },
    {
      "nct_id": "NCT01299649",
      "title": "Retrospective Safety Study to Compare Mortality in Intensive Care Unite (ICU) Patients Undergoing Echocardiography With or Without DEFINITY®",
      "overall_status": "COMPLETED",
      "study_type": "OBSERVATIONAL",
      "phases": [],
      "conditions": [
        "Cardiovascular Disease"
      ],
      "interventions": [],
      "intervention_types": [],
      "sponsor": "Lantheus Medical Imaging",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 4300000,
      "start_date": "2008-06",
      "completion_date": "2008-12",
      "has_results": false,
      "last_update_posted_date": "2020-11-10",
      "last_synced_at": "2026-10-17T11:57:59.047Z",
      "location_count": 1,
      "location_summary": "North Billerica, Massachusetts",
      "locations": [
        {
          "city": "North Billerica",
          "state": "Massachusetts"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01299649"
    },
    {
      "nct_id": "NCT04599855",
      "title": "A Study of Esketamine Nasal Spray, Administered as Monotherapy, in Adult Participants With Treatment-resistant Depression",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE4"
      ],
      "conditions": [
        "Depressive Disorder, Treatment-Resistant"
      ],
      "interventions": [
        {
          "name": "Esketamine 56 mg",
          "type": "DRUG"
        },
        {
          "name": "Esketamine 84 mg",
          "type": "DRUG"
        },
        {
          "name": "Placebo",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Janssen Research & Development, LLC",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 477,
      "start_date": "2020-11-04",
      "completion_date": "2024-01-31",
      "has_results": true,
      "last_update_posted_date": "2025-04-25",
      "last_synced_at": "2026-10-17T11:57:59.047Z",
      "location_count": 54,
      "location_summary": "Birmingham, Alabama • Huntsville, Alabama • Little Rock, Arkansas + 44 more",
      "locations": [
        {
          "city": "Birmingham",
          "state": "Alabama"
        },
        {
          "city": "Huntsville",
          "state": "Alabama"
        },
        {
          "city": "Little Rock",
          "state": "Arkansas"
        },
        {
          "city": "Glendale",
          "state": "California"
        },
        {
          "city": "Los Angeles",
          "state": "California"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT04599855"
    },
    {
      "nct_id": "NCT01931904",
      "title": "Eye Pressure Lowering Surgery",
      "overall_status": "ACTIVE_NOT_RECRUITING",
      "study_type": "OBSERVATIONAL",
      "phases": [],
      "conditions": [
        "Glaucoma"
      ],
      "interventions": [],
      "intervention_types": [],
      "sponsor": "Oregon Health and Science University",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "85 Years",
        "sex": "ALL",
        "summary": "18 Years to 85 Years"
      },
      "enrollment_count": 21,
      "start_date": "2014-02-01",
      "completion_date": "2031-05-31",
      "has_results": false,
      "last_update_posted_date": "2026-09-02",
      "last_synced_at": "2026-10-17T11:57:59.047Z",
      "location_count": 1,
      "location_summary": "Portland, Oregon",
      "locations": [
        {
          "city": "Portland",
          "state": "Oregon"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01931904"
    },
    {
      "nct_id": "NCT05374616",
      "title": "Natural History Study and Establishment of a Biorepository-TANGO2-related Disorder",
      "overall_status": "RECRUITING",
      "study_type": "OBSERVATIONAL",
      "phases": [],
      "conditions": [
        "TANGO2-related Disorder"
      ],
      "interventions": [
        {
          "name": "Observation",
          "type": "GENETIC"
        }
      ],
      "intervention_types": [
        "GENETIC"
      ],
      "sponsor": "Baylor College of Medicine",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "0 Days",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "0 Days and older"
      },
      "enrollment_count": 300,
      "start_date": "2018-05-18",
      "completion_date": "2030-01-01",
      "has_results": false,
      "last_update_posted_date": "2025-10-01",
      "last_synced_at": "2026-10-17T11:57:59.047Z",
      "location_count": 1,
      "location_summary": "Houston, Texas",
      "locations": [
        {
          "city": "Houston",
          "state": "Texas"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT05374616"
    },
    {
      "nct_id": "NCT01555606",
      "title": "An Observational Study to Evaluate Patient-Reported Experiences of Living With Moderate-to-Severe Plaque Psoriasis",
      "overall_status": "COMPLETED",
      "study_type": "OBSERVATIONAL",
      "phases": [],
      "conditions": [
        "Moderate to Severe Plaque Psoriasis"
      ],
      "interventions": [
        {
          "name": "No intervention",
          "type": "OTHER"
        }
      ],
      "intervention_types": [
        "OTHER"
      ],
      "sponsor": "Janssen Biotech, Inc.",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 108,
      "start_date": "2011-06",
      "completion_date": "2012-07",
      "has_results": false,
      "last_update_posted_date": "2015-07-21",
      "last_synced_at": "2026-10-17T11:57:59.047Z",
      "location_count": 9,
      "location_summary": "Phoenix, Arizona • Sacramento, California • Ann Arbor, Michigan + 6 more",
      "locations": [
        {
          "city": "Phoenix",
          "state": "Arizona"
        },
        {
          "city": "Sacramento",
          "state": "California"
        },
        {
          "city": "Ann Arbor",
          "state": "Michigan"
        },
        {
          "city": "East Windsor",
          "state": "New Jersey"
        },
        {
          "city": "Stony Brook",
          "state": "New York"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01555606"
    },
    {
      "nct_id": "NCT06212947",
      "title": "A Multicenter Multinational Observational Study of Children With Hypochondroplasia",
      "overall_status": "RECRUITING",
      "study_type": "OBSERVATIONAL",
      "phases": [],
      "conditions": [
        "Hypochondroplasia"
      ],
      "interventions": [],
      "intervention_types": [],
      "sponsor": "BioMarin Pharmaceutical",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": null,
        "maximum_age": "15 Years",
        "sex": "ALL",
        "summary": "Up to 15 Years"
      },
      "enrollment_count": 400,
      "start_date": "2023-11-27",
      "completion_date": "2043-12-31",
      "has_results": false,
      "last_update_posted_date": "2025-04-03",
      "last_synced_at": "2026-10-17T11:57:59.047Z",
      "location_count": 16,
      "location_summary": "Phoenix, Arizona • Los Angeles, California • Oakland, California + 13 more",
      "locations": [
        {
          "city": "Phoenix",
          "state": "Arizona"
        },
        {
          "city": "Los Angeles",
          "state": "California"
        },
        {
          "city": "Oakland",
          "state": "California"
        },
        {
          "city": "Wilmington",
          "state": "Delaware"
        },
        {
          "city": "Washington D.C.",
          "state": "District of Columbia"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT06212947"
    }
  ]
}